Cladogenesis is an evolutionary splitting event in which each branch and its smaller branches forms a "clade", an evolutionary mechanism and a process of adaptive evolution that leads to the development of a greater variety of sister organisms.

Cladogenesis is often contrasted with anagenesis, where gradual changes in an ancestral species lead to its eventual "replacement" by a novel form (i.e, there is no "splitting" of the phylogenetic tree.).